Semiconductor light-emitting device including a reflector layer having a multi-layered structure

ABSTRACT

A semiconductor light-emitting device includes a light-emitting structure including a first semiconductor layer, an active layer, and a second semiconductor layer which are sequentially stacked, a first insulating layer on the second semiconductor layer with a plurality of first openings having first widths and a plurality of second openings having second widths different from the first widths, a first electrode electrically connected to the first semiconductor layer through the first openings, a first sub-electrode layer between the second semiconductor layer and the first insulating layer, the first sub-electrode layer being exposed through the second openings, and a second sub-electrode layer on the first insulating layer, the second sub-electrode layer being connected to the first sub-electrode layer through the second openings, wherein a first distance between the first openings closest to each other is different from a second distance between the second openings closest to each other.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation application based on pending application Ser. No.15/718,438, filed Sep. 28, 2017, the entire contents of which is herebyincorporated by reference.

Korean Patent Application No. 10-2016-0152800, filed on Nov. 16, 2016,in the Korean Intellectual Property Office, and entitled: “SemiconductorLight-Emitting Device Including a Reflector Layer Having a Multi-LayeredStructure,” is incorporated by reference herein in its entirety.

BACKGROUND 1. Field

Embodiments relate to a semiconductor light-emitting device and, moreparticularly, to a semiconductor light-emitting device including areflector layer having a multi-layered structure.

2. Description of the Related Art

A semiconductor light-emitting device, e.g., a light-emitting diode, maybe a device of which a material emits light. In the semiconductorlight-emitting device, electrons and holes of a junction-typesemiconductor are recombined with each other to generate energy, and thegenerated energy may be converted into light. The converted light may beemitted from the semiconductor light-emitting device. The semiconductorlight-emitting devices are widely used in, e.g., lighting apparatuses,display devices, and light sources, and the development thereof isaccelerating.

In particular, gallium nitride (GaN)-based light-emitting diodes havebeen commercialized, e.g., in keypads for portable phones, turn signallamps, and flashes of cameras. In addition, general light apparatuseshave been developed using light-emitting diodes. Furthermore, thelight-emitting diodes have been used in large-sized applicationproducts, e.g., backlight units of large-sized televisions and vehicleheadlights.

SUMMARY

In an aspect, a semiconductor light-emitting device may include alight-emitting structure including a first semiconductor layer, anactive layer and a second semiconductor layer which are sequentiallystacked, a first insulating layer disposed on the second semiconductorlayer, the first insulating layer including a plurality of firstopenings, each of which has a first width, and a plurality of secondopenings, each of which has a second width different from the firstwidth, a first electrode electrically connected to the firstsemiconductor layer through the first openings, a first sub-electrodelayer disposed between the second semiconductor layer and the firstinsulating layer and exposed through the second openings, and a secondsub-electrode layer disposed on the first insulating layer and connectedto the first sub-electrode layer through the second openings. A firstdistance between the first openings closest to each other may bedifferent from a second distance between the second openings closest toeach other.

In an aspect, a semiconductor light-emitting device may include a growthsubstrate, a light-emitting structure including a first semiconductorlayer, an active layer and a second semiconductor layer which aresequentially stacked on the growth substrate, the light-emittingstructure including first regions exposing the first semiconductor layerand a second region thicker than the first regions, a transparentelectrode layer disposed on the second region and being in contact withthe second semiconductor layer, a first insulating layer disposed on thefirst and second regions and having first openings exposing the firstsemiconductor layer and second openings exposing the transparentelectrode layer, a reflective metal layer being in contact with thefirst semiconductor layer exposed through the first openings, and asub-electrode layer disposed on the first insulating layer on the secondregion. The sub-electrode layer may be in contact with the transparentelectrode layer exposed through the second openings. A first width ofeach of the first openings may be greater than a second width of each ofthe second openings, and a first distance between the first openingsclosest to each other may be greater than a second distance between thesecond openings closest to each other.

In an aspect, a semiconductor light-emitting device may include alight-emitting structure including a first semiconductor layer, anactive layer and a second semiconductor layer which are sequentiallystacked, a first electrode on the second semiconductor layer, a secondelectrode between the second semiconductor layer and the firstelectrode, and connection contacts disposed in first openings whichpenetrate the second electrode, the second semiconductor layer, and theactive layer to expose the first semiconductor layer. The secondelectrode may include a transparent electrode layer being in contactwith the second semiconductor layer, a first insulating layer disposedon the transparent electrode layer and including a plurality of secondopenings exposing the transparent electrode layer, and a reflectivemetal layer disposed on the first insulating layer and extending intothe second openings so as to be in contact with the transparentelectrode layer. The first openings may be two-dimensionally arrangedand the second openings may be two-dimensionally arranged. A first widthof each of the first openings may be greater than a second width of eachof the second openings, and a first distance between the first openingsclosest to each other may be greater than a second distance between thesecond openings closest to each other.

In an aspect, a semiconductor light-emitting device may include alight-emitting structure including a first semiconductor layer, anactive layer, and a second semiconductor layer which are sequentiallystacked, a first insulating layer on the second semiconductor layer, thefirst insulating layer including a plurality of first openings havingfirst widths, and a plurality of second openings having second widthsdifferent from the first width a first electrode electrically connectedto the first semiconductor layer through the first openings, a firstsub-electrode layer between the second semiconductor layer and the firstinsulating layer, the first sub-electrode layer being exposed throughthe second openings, and a second sub-electrode layer on the firstinsulating layer, the second sub-electrode layer being connected to thefirst sub-electrode layer through the second openings, wherein a firstdistance between first openings directly adjacent to each other isdifferent from a second distance between second openings directlyadjacent to each other.

BRIEF DESCRIPTION OF THE DRAWINGS

Features will become apparent to those of ordinary skill in the art bydescribing in detail exemplary embodiments with reference to theattached drawings, in which:

FIGS. 1A and 1B illustrate schematic cross-sectional views ofsemiconductor light-emitting device packages according to someembodiments.

FIG. 2A illustrates a schematic plan view of a semiconductorlight-emitting device according to some embodiments.

FIG. 2B illustrates an enlarged view of portion ‘M’ of FIG. 2A.

FIG. 3A illustrates a cross-sectional view along line I-I′ of FIG. 2B.

FIG. 3B illustrates a cross-sectional view along lines A-A′ and B-B′ ofFIG. 2A.

FIGS. 4A to 4C illustrate enlarged views corresponding to portion ‘A’ ofFIG. 3A.

FIGS. 5A to 5C illustrate plan views of a portion of a first insulatinglayer of FIG. 3A.

FIG. 6 illustrates a graph of light efficiency of a semiconductorlight-emitting device according to a width and a pitch of secondopenings of a first insulating layer.

FIGS. 7 to 12 illustrate cross-sectional views along line I-I′ of FIG.2B of stages in a method for manufacturing a semiconductorlight-emitting device, according to some embodiments.

FIG. 13 illustrates a schematic cross-sectional view of a semiconductorlight-emitting device package according to some embodiments.

FIG. 14 illustrates a schematic plan view of a semiconductorlight-emitting device according to some embodiments.

FIG. 15 illustrates a cross-sectional view along line II-II′ of FIG. 14.

FIGS. 16 to 21 illustrate cross-sectional views along line II-II′ ofFIG. 14 of stages in a method for manufacturing a semiconductorlight-emitting device, according to some embodiments.

FIG. 22 illustrates a cross-sectional view corresponding to line II-II′of FIG. 14 of a semiconductor light-emitting device according to someembodiments.

FIGS. 23 to 25 illustrate cross-sectional views corresponding to lineII-II′ of FIG. 14 of stages in a method for manufacturing asemiconductor light-emitting device, according to some embodiments.

DETAILED DESCRIPTION

Embodiments will be described hereinafter in detail with reference tothe accompanying drawings.

FIGS. 1A and 1B are schematic cross-sectional views illustratingsemiconductor light-emitting device packages according to someembodiments.

Referring to FIG. 1A, a semiconductor light-emitting device package 1 aaccording to some embodiments may include a package body 10, a pair oflead frames 12 and 14, a semiconductor light-emitting device 20, and asealing layer 30. The pair of lead frames 12 and 14 may include a firstlead frame 12 and a second lead frame 14.

The semiconductor light-emitting device 20 may include a light-emittingstructure 110 and an electrode structure 160 which are sequentiallystacked on a growth substrate 100. The light-emitting structure 110 mayinclude first and second semiconductor layers 112 and 116 havingdifferent conductivity types, and an active layer 114 disposed betweenthe first and second semiconductor layers 112 and 116, e.g., the firstsemiconductor layer 112 may be between the active layer 114 and thegrowth substrate 100. The electrode structure 160 may include electrodesrespectively connected to the first and second semiconductor layers 112and 116, and under-bump metallurgy (UBM) patterns 152 and 154electrically connected to the electrodes.

The semiconductor light-emitting device 20 may be mounted on the firstand second lead frames 12 and 14 through respective connecting terminals42 and 44, which are bonded to the UBM patterns 152 and 154,respectively. For example, a first UBM pattern 152 may be electricallyconnected to the first lead frame 12 through a first connecting terminal42, and a second UBM pattern 154 may be electrically connected to thesecond lead frame 14 through a second connecting terminal 44. Theconnecting terminals 42 and 44 may include, e.g., bumps or solder balls.Each of the first and second UBM patterns 152 and 154 may be provided insingular or plural.

The package body 10 may include a reflective cup 11 for improvingreflection efficiency and extraction efficiency of light. The sealinglayer 30 formed of a transparent material may be disposed in thereflective cup 11 to seal the semiconductor light-emitting device 20.The sealing layer 30 may include a resin in which a fluorescentsubstance is dispersed. The fluorescent substance may include, e.g., agreen fluorescent substance and/or a red fluorescent substance.

Electron-hole recombination may occur in the active layer 114 by anelectrical signal provided through the electrode structure 160. Lightgenerated by the electron-hole recombination may be emitted upwardthrough the growth substrate 100. In other words, the semiconductorlight-emitting device 20 may have a flip-chip structure emitting lightthrough the growth substrate 100.

Referring to FIG. 1B, a semiconductor light-emitting device package 1 bmay include a mounting substrate 10 a, the semiconductor light-emittingdevice 20, and the sealing layer 30. The semiconductor light-emittingdevice 20 may be the same as described with reference to FIG. 1A, andthus the descriptions thereof will be omitted.

The semiconductor light-emitting device 20 may be mounted on themounting substrate 10 a so as to be electrically connected to first andsecond circuit patterns 16 and 18. For example, the first UBM pattern152 may be electrically connected to the first circuit pattern 16through the first connecting terminal 42, and the second UBM pattern 154may be electrically connected to the second circuit pattern 18 throughthe second connecting terminal 44. For example, the mounting substrate10 a may be a printed circuit board (PCB), a metal core PCB (MCPCB), amulti-layered PCB (MPCB), or a flexible PCB (FPCB). In certainembodiments, the structure of the mounting substrate 10 a may bevariously applied. The semiconductor light-emitting device 20 may besealed by the sealing layer 30. Thus, a chip-on-board (COB)-type packagestructure may be realized.

In the present specification, spatially relative terms, such as“beneath”, “below”, “lower”, “above”, “upper” and the like, may be usedherein for ease of description to describe one element or feature'srelationship to another element(s) or feature(s) as illustrated in thefigures. It will be understood that the spatially relative terms areintended to encompass different orientations of the device in use oroperation in addition to the orientation depicted in the figures. Thesemiconductor light-emitting device 20 according to some embodimentswill be described hereinafter in more detail.

FIG. 2A is a schematic plan view illustrating the semiconductorlight-emitting device 20, and FIG. 2B is an enlarged view of portion ‘M’of FIG. 2A. FIG. 3A is a cross-sectional view taken along line I-I′ ofFIG. 2B, and FIG. 3B is a cross-sectional view taken along lines A-A′and B-B′ of FIG. 2A. FIGS. 4A to 4C are enlarged views corresponding toportion ‘A’ of FIG. 3A. FIGS. 5A to 5C are plan views illustrating aportion of a first insulating layer of FIG. 3A. FIG. 6 is a graphillustrating light efficiency of a semiconductor light-emitting deviceaccording to a width and a pitch of second openings of a firstinsulating layer.

Referring to FIGS. 2A, 2B, 3A, 3B, and 4A, the semiconductorlight-emitting device 20 may include the growth substrate 100 and thelight-emitting structure 110 including the first semiconductor layer112, the active layer 114, and the second semiconductor layer 116sequentially stacked on the growth substrate 100. A buffer layer may bedisposed between the growth substrate 100 and the first semiconductorlayer 112 to relax stress generated by lattice mismatch between thegrowth substrate 100 and the first semiconductor layer 112. The growthsubstrate 100 may be a transparent substrate, e.g., a sapphiresubstrate.

The first semiconductor layer 112 may be formed of a semiconductormaterial doped with N-type dopants and may be, e.g., an N-type nitridesemiconductor layer. The second semiconductor layer 116 may be formed ofa semiconductor material doped with P-type dopants and may be, e.g., aP-type nitride semiconductor layer. The first and second semiconductorlayers 112 and 116 may have a composition formula ofAl_(x)In_(y)Ga_((1-x-y))N (where 0≤x≤1, 0≤y≤1, and 0≤x+y≤1) and mayinclude, e.g., GaN, AlGaN, InGaN, or AlInGaN.

The active layer 114 disposed between the first and second semiconductorlayers 112 and 116 may emit light having a predetermined energy byrecombination of electrons and holes. The active layer 114 may include amaterial of which an energy band gap is smaller than those of the firstand second semiconductor layers 112 and 116. For example, when the firstand second semiconductor layers 112 and 116 are formed of a GaN-basedcompound semiconductor, the active layer 114 may include an InGaN-basedcompound semiconductor of which an energy band gap is smaller than thatof the GaN-based compound semiconductor. The active layer 114 may have amultiple quantum well (MQW) structure in which quantum well layers andquantum barrier layers are alternately stacked, e.g., an InGaN/GaNstructure. However, embodiments are not limited thereto. In certainembodiments, the active layer 114 may have a single quantum well (SQW)structure.

The light-emitting structure 110 may include a first region R1 and asecond region R2. The first region R1 may correspond to an etched regionof the light-emitting structure 110, in which the second semiconductorlayer 116 and the active layer 114 are etched to expose a top surface ofthe first semiconductor layer 112. The second region R2 may correspondto a mesa region of the light-emitting structure 110, which is notetched during the formation of the first region R1. A sidewall of thesecond region R2 may be inclined downward toward the growth substrate100.

A first sub-electrode layer 122 may be disposed on the second region R2of the light-emitting structure 110. The first sub-electrode layer 122may be in, e.g., direct, contact with a top surface of the secondsemiconductor layer 116. In some embodiments, a sidewall of the firstsub-electrode layer 122 may have a profile which is continuous with thesidewall of the second region R2, e.g., lateral sidewalls of the firstsub-electrode layer 122 and the second semiconductor layer 116 may becoplanar. The first sub-electrode layer 122 may be a transparentelectrode layer. For example, the first sub-electrode layer 122 mayinclude a transparent conductive oxide, e.g., indium-tin oxide (ITO),indium-zinc oxide (IZO), or indium-tin-zinc oxide (ITZO).

A first insulating layer 124 may be disposed on the first and secondregions R1 and R2 of the light-emitting structure 110. The firstinsulating layer 124 may cover a top surface and the sidewalls of thefirst sub-electrode layer 122, the sidewalls of the second region R2,e.g., sidewalls of the second semiconductor layer 116 and of the activelayer 114, and a top surface of the first region R, e.g., the topsurface of the first semiconductor layer 112. The first insulating layer124 may be formed of an insulating material of which a refractive indexis lower than that of the second semiconductor layer 116. In someembodiments, the first insulating layer 124 may be a single layer formedof a silicon oxide (SiO₂) layer. In certain embodiments, the firstinsulating layer 124 may have a structure in which first sub-insulatinglayers 124 a and second sub-insulating layers 124 b are alternatelyrepeatedly stacked, as illustrated in FIG. 4A. Here, refractive indexesof the first and second sub-insulating layers 124 a and 124 b may belower than the refractive index of the second semiconductor layer 116and may be different from each other. For example, the firstsub-insulating layer 124 a may be formed of a silicon oxide (SiO₂)layer, and the second sub-insulating layer 124 b may be formed of atitanium oxide (TiO₂) layer or a niobium oxide (Nb₂O₅) layer. Thus, thefirst insulating layer 124 may have an omnidirectional reflective (ODR)structure or a distributed Bragg reflective (DBR) structure.

The first insulating layer 124 may have a plurality of openings OP1 andOP2. The plurality of openings OP1 and OP2 may include a first openingOP1 and a second opening OP2, which have widths different from eachother. The first and second openings OP1 and OP2 may have opened-holeshapes completely penetrating the first insulating layer 124. The firstopening OP1 may penetrate the first insulating layer 124 disposed on thefirst region R1 of the light-emitting structure 110 to expose the topsurface of the first semiconductor layer 112. The second opening OP2 maypenetrate the first insulating layer 124 disposed on the second regionR2 of the light-emitting structure 110 to expose the top surface of thefirst sub-electrode layer 122. The first opening OP1 may be used as aconnection path through which a first electrode 130 a (to be describedlater) is connected to the first semiconductor layer 112, and the secondopening OP2 may be used as a connection path through which a secondsub-electrode layer 126 (to be described later) is connected to thefirst sub-electrode layer 122.

Each of the first and second openings OP1 and OP2 may have a, e.g.,circular, planar shape. However, embodiments are not limited thereto. Incertain embodiments, one or all of the first and second openings OP1 andOP2 may have a polygonal planar shape, e.g., a quadrilateral planarshape. The first opening OP1 may have a first width W1 (or a firstdiameter), and the second opening OP2 may have a second width W2 (or asecond diameter). As illustrated in FIGS. 3A and 4A, each of the firstand second openings OP1 and OP2 may have a width which becomesprogressively smaller toward the growth substrate 100, e.g., the W1 andW2 decrease as a distance from the growth substrate 100 decreases. Atthis time, the first width W1 may correspond to the minimum width of thefirst opening OP1 (i.e., a width of a bottom end of the first openingOP1). Likewise, the second width W2 may correspond to the minimum widthof the second opening OP2 (i.e., a width of a bottom end of the secondopening OP2). In some embodiments, the second width W2 may be smallerthan 10 μm, e.g., the second width W2 may be equal to or greater than 1μm and smaller than 10 μm. The first width W1 may be greater than thesecond width W2.

Each of the first and second openings OP1 and OP2 may be provided inplurality. The plurality of first openings OP1 may be two-dimensionallyarranged. For example, as illustrated in FIG. 2A, the plurality of firstopenings OP1 may be arranged in a first direction D1 and a seconddirection D2 intersecting (e.g., perpendicular to) the first directionD1 to constitute a plurality of rows and a plurality of columns. At thistime, distances, each of which is between the first openings OP1adjacent to each other in the first direction D1 or the second directionD2, may be equal to each other or different from each other. Forexample, as illustrated in FIG. 2B, the plurality of second openings OP2may be two-dimensionally arranged, and may be arranged at equaldistances along the first direction D1 and/or the second direction D2.The widths and the arrangement relationships of the first and secondopenings OP1 and OP2 may influence current diffusion and lightextraction efficiency. Thus, the widths and the arrangementrelationships of the first and second openings OP1 and OP2 may belimited to improve the current diffusion and the light extractionefficiency. In the present specification, a distance or a pitch ofopenings may be defined as a distance between centers of openingsadjacent to each other. The widths and the arrangement relationships ofthe first and second openings OP1 and OP2 will be described later inmore detail.

In some embodiments, the first insulating layer 124 may further includeconnection openings COP. Each of the connection openings COP may connectthe first openings OP1 adjacent to each other in the second directionD2. The connection opening COP may be disposed between the firstopenings OP1 adjacent to each other in the second direction D2 to have along shape in the second direction D2, when viewed in a plan view. Awidth of the connection opening COP in the first direction D1 may besmaller than the first width W1 of the first opening OP1.

A second sub-electrode layer 126 may be disposed on the second region R2of the light-emitting structure 110. On the second region R2, the secondsub-electrode layer 126 may cover the top surface of the firstinsulating layer 124 and may extend into the second openings OP2. Thesecond sub-electrode layer 126 may be in contact with the firstsub-electrode layer 122 exposed through the second openings OP2. In someembodiments, the second sub-electrode layer 126 may partially fill thesecond openings OP2. In other words, the second sub-electrode layer 126may conformally cover the top surface of the first insulating layer 124and inner surfaces of the second openings OP2. In certain embodiments,the second sub-electrode layer 126 may completely fill the secondopenings OP2, as illustrated in FIG. 4B. When the second width W2 issmall (i.e., the second openings OP2 are narrow), the second openingsOP2 may be completely filled with the second sub-electrode layer 126during the formation of the second sub-electrode layer 126. The secondsub-electrode layer 126 may include a reflective metal material, e.g.,silver (Ag) or aluminum (Al). In particular, the second sub-electrodelayer 126 may include silver (Ag).

In certain embodiments, an additional transparent electrode layer 122 amay be disposed between the first insulating layer 124 and the secondsub-electrode layer 126 and between the first sub-electrode layer 122and the second sub-electrode layer 126, as illustrated in FIG. 4C. Inother words, the additional transparent electrode layer 122 a may bedisposed under the second sub-electrode layer 126 to conformally coverthe top surface of the first insulating layer 124 and the inner surfacesof the second openings OP2. The additional transparent electrode layer122 a may include the same material as the first sub-electrode layer122.

A second insulating layer 128 may be disposed on the first and secondregions R1 and R2 of the light-emitting structure 110. The secondinsulating layer 128 may cover the second sub-electrode layer 126 andthe first insulating layer 124 exposed by the second sub-electrode layer126. The second insulating layer 128 may include sidewalls havingprofiles which are continuous with sidewalls of the first openings OP1.In other words, the first openings OP1 may extend into the secondinsulating layer 128 to penetrate the second insulating layer 128. Thesecond insulating layer 128 may include at least one third opening OP3exposing a portion of the second sub-electrode layer 126. The secondinsulating layer 128 may include, e.g., a silicon oxide layer.

Reflective metal layers 130 a and 130 b may be disposed on the secondinsulating layer 128 overlapping with the second region R2. Thereflective metal layers 130 a and 130 b may include a first reflectivemetal layer 130 a connected to the first semiconductor layer 112 exposedthrough the first opening OP1, and a second reflective metal layer 130 bconnected to the second sub-electrode layer 126 exposed through thethird opening OP3. The first reflective metal layer 130 a may extendonto the first region R1 to partially fill the first opening OP1. Inother words, the first reflective metal layer 130 a may be in, e.g.,direct, contact with the first semiconductor layer 112 exposed throughthe first opening OP1. In addition, the first reflective metal layer 130a may conformally cover an inner surface of the first opening OP1. Thesecond reflective metal layer 130 b may be electrically insulated fromthe first reflective metal layer 130 a and the first semiconductor layer112. The first and second reflective metal layers 130 a and 130 b mayinclude a reflective metal material, e.g., silver (Ag) or aluminum (Al).In particular, the first and second reflective metal layers 130 a and130 b may include aluminum (Al).

A first metal interconnection 142 may be disposed on the firstreflective metal layer 130 a and may be in contact with the firstreflective metal layer 130 a. The first metal interconnection 142 maycompletely or partially fill the first opening OP1 in which the firstreflective metal layer 130 a is disposed. A second metal interconnection144 may be disposed on the second reflective metal layer 130 b and maybe in contact with the second reflective metal layer 130 b. The secondmetal interconnection 144 may completely or partially fill the thirdopening OP3 in which the second reflective metal layer 130 b isdisposed. The first and second metal interconnections 142 and 144 mayinclude at least one of, e.g., aluminum (Al), chromium (Cr), titanium(Ti), copper (Cu), or any alloy thereof.

As illustrated in FIG. 3B, a protection layer 150 may be disposed on thefirst and second metal interconnections 142 and 144. The protectionlayer 150 may partially expose each of the first and second metalinterconnections 142 and 144. The protection layer 150 may include apassivation insulating layer, e.g., a silicon oxide layer and/or asilicon nitride layer.

A first UBM pattern 152 and a second UBM pattern 154 may be disposed onthe first and second metal interconnections 142 and 144 exposed by theprotection layer 150, respectively. Thus, the first UBM pattern 152 maybe electrically connected to the first semiconductor layer 112 throughthe first metal interconnection 142 and the first reflective metal layer130 a. The second UBM pattern 154 may be electrically connected to thesecond semiconductor layer 116 through the second metal interconnection144, the second reflective metal layer 130 b, the second sub-electrodelayer 126, and the first sub-electrode layer 122. The first and secondUBM patterns 152 and 154 may include a single metal or alloy includingat least one of, e.g., titanium (Ti), tungsten-titanium (TiW), chromium(Cr), copper (Cu), nickel (Ni), gold (Au), lead (Pd), or silver (Ag).

The first reflective metal layer 130 a, which is connected to the firstsemiconductor layer 112 and is electrically connected to the first UBMpattern 152 through the first metal interconnection 142, may be definedas a first electrode 130 a. The first insulating layer 124 and the firstand second sub-electrode layers 122 and 126 connected to each otherthrough the second openings OP2 of the first insulating layer 124 may bedefined as a second electrode 120. The second electrode 120 may be incontact with the second semiconductor layer 116 and may be electricallyconnected to the second UBM pattern 154 through the second reflectivemetal layer 130 b and the second metal interconnection 144. Thesub-electrode layers 122 and 126, the reflective metal layers 130 a and130 b, the metal interconnections 142 and 144, the insulating layers 124and 128, the protection layer 150, and the UBM patterns 152 and 154 mayconstitute the electrode structure 160 of FIG. 1.

According to some embodiments, a reflector layer having a multi-layeredstructure including the sub-electrode layers 122 and 126, the insulatinglayers 124 and 128, and the reflective metal layers 130 a and 130 b maybe provided on the light-emitting structure 110. Thus, reflectivity ofthe semiconductor light-emitting device 20 may be improved to increasethe light extraction efficiency. In particular, the first insulatinglayer 124 may have a lower refractive index than the secondsemiconductor layer 116 and/or may have the ODR or DBR structure. Thus,when the light emitted from the active layer 114 reaches the firstinsulating layer 124, the amount of light reflection may be larger thanthe amount of light absorption. In addition, as illustrated in FIG. 3B,the first insulating layer 124 may extend onto the first region R1formed along an edge of the light-emitting structure 110, and thus ahigh-reflection region may be realized in an entire region of thelight-emitting structure 110.

On the other hand, when areas of the first and second openings OP1 andOP2 increase, an area of the first insulating layer 124 may decrease buta contact area of the first semiconductor layer 112 and the firstreflective metal layer 130 a and a contact area of the first and secondsub-electrode layers 122 and 126 may increase. In other words, theincrease in area of the first and second openings OP1 and OP2 may reducean operating voltage to improve electrical characteristics of thesemiconductor light-emitting device 20 but may cause the reduction ofthe reflectivity of the semiconductor light-emitting device 20 to reducethe light extraction efficiency of the semiconductor light-emittingdevice 20. Thus, the areas of the first and second openings OP1 and OP2may be properly limited to harmonize the light extraction efficiency andthe electrical characteristics which are in a trade-off relationship.

The areas of the first and second openings OP1 and OP2 may be adjustedby the widths and the arrangement relationships of the first and secondopenings OP1 and OP2. According to some embodiments, the first openingsOP1 may have a smaller total area than the second openings OP2 inconsideration of characteristics of the first semiconductor layer 112having a lower electrical resistance than the second semiconductor layer116. For example, as illustrated in FIG. 2B, the first width W1 of thefirst openings OP1 may be greater than the second width W2 of the secondopenings OP2. However, a first distance between the first openings OP1adjacent to each other (e.g., a first pitch P1 between the firstopenings OP1 adjacent to each other in the second direction D2 in FIG.2B) may be greater than a second distance between the second openingsOP2 (e.g., a second pitch P2 between the second openings OP2 adjacent toeach other in the first and/or second direction D1 and D2 in FIG. 2).Thus, a total number of the first openings OP1 may be much smaller thana total number of the second openings OP2. As a result, the total areaof the first openings OP1 may be smaller than a total area of the secondopenings OP2. Here, the total area of the first openings OP1 may be asum of the areas of the first openings OP1, and the total area of thesecond openings OP2 may be a sum of the areas of the second openingsOP2. For example, if the first and second openings OP1 and OP2 havecircular shapes in plan view, an area of one opening may be an are of awidest circle in each opening, i.e., as measured at the top of theopening with the largest diameter.

In addition, the distances between the first openings OP1 may be equalto each other, or the first openings OP1 may be randomly distributed. Onthe other hand, the second openings OP2 may be arranged at equaldistances. In some embodiments, as illustrated in FIG. 5A, the secondopenings OP2 may be arranged in the first direction D1 and the seconddirection D2 intersecting (e.g., perpendicular to) the first directionD1 to constitute a plurality of rows and a plurality of columns. At thistime, the second distance P2 between the second openings OP2 adjacent toeach other in the first direction D1 or the second direction D2 may beconstant. The second distance P2 may be defined as a distance betweencenters of the second openings OP2 adjacent to each other in the firstdirection D1 or the second direction D2 when viewed in a plan view. Inthe present embodiment, the centers of four second openings OP2 adjacentto each other may form a square.

In certain embodiments, as illustrated in FIG. 5B, the second openingsOP2 may be arranged in a zigzag form along the first direction D1 andthe second direction D2. In other words, the second openings OP2 may bearranged in a honeycomb form when viewed in a plan view. At this time,second distances d, each of which is between the second openings OP2closest to each other, may be equal to each other. In the presentembodiment, centers of the second openings OP2 arranged in a triangularform may form an equilateral triangle.

In certain embodiments, as illustrated in FIG. 5C, each of the secondopenings OP2 may have a polygonal planar shape such as a quadrilateralshape. For example, each of the first openings OP1 may have a polygonalplanar shape such as a quadrilateral shape.

According to some embodiments, the second width W2 of the secondopenings OP2 may be smaller than 10 μm to achieve a desired lightefficiency (lm/W) of the semiconductor light-emitting device 20. Here,the light efficiency (lm/W) may be defined as a value obtained bydividing a luminous flux (lm) of the semiconductor light-emitting device20 by a power consumption (W). In some embodiments, each of the secondopenings OP2 may have a circular planar shape, and the second width W2may be equal to or greater than 1 μm and smaller than 10 μm. Inaddition, the second distance P2 or d between the second openings OP2adjacent to each other may range from about 10 μm to about 50 μm. On theother hand, some of the second openings OP2 may be regularly andasymmetrically arranged in a local area to avoid overlap with astructure of another layer.

When the second width W2 of the second openings OP2 is increased toincrease the total area of the second openings OP2, both the luminousflux (lm) and the power consumption (W) may be reduced. When the seconddistance P2 or d between the second openings OP2 is increased to reducethe total area of the second openings OP2, both the luminous flux (lm)and the power consumption (W) may be increased. Thus, the second widthW2 and the second distance P2 or d of the second openings OP2 may beproperly limited to achieve the desired light efficiency (lm/W).

As illustrated in FIG. 6, in the case in which the width of the secondopening OP2 is 10 μm, a desired light efficiency value T is not achievedregardless of the distance (i.e., the pitch) between the second openingsOP2. On the contrary, when the second width W2 of the second opening OP2is smaller than 10 μm, the desired light efficiency value T can beachieved in the case in which the second distance P2 or d between thesecond openings OP2 ranges from about 10 μm to about 50 μm. As a result,to achieve the desired light efficiency (lm/W) of the semiconductorlight-emitting device 20, the second openings OP2 may have the secondwidth W2 being equal to or greater than 1 μm and smaller than 10 μm andthe second distance P2 or d ranging from about 10 μm to about 50 μm. Amethod for manufacturing the semiconductor light-emitting device 20 willbe described hereinafter.

FIGS. 7 to 12 are cross-sectional views taken along line I-I′ of FIG. 2Bto illustrate stages in a method for manufacturing a semiconductorlight-emitting device, according to some embodiments. Hereinafter, thesame descriptions as explained above will be omitted or mentioned onlybriefly for the purpose of ease and convenience in explanation.

Referring to FIGS. 2B and 7, the light-emitting structure 110 may beformed on a growth substrate 100. The light-emitting structure 110 mayinclude the first semiconductor layer 112, the active layer 114, and thesecond semiconductor layer 116, which are sequentially stacked on thegrowth substrate 100. For example, the first semiconductor layer 112 maybe formed of P-type GaN, and the second semiconductor layer 116 may beformed of N-type GaN. For example, the active layer 114 may be formed byalternately stacking quantum well layers formed of InGaN and quantumbarrier layers formed of GaN. Each of the first semiconductor layer 112,the active layer 114, and the second semiconductor layer 116 may beformed by a process, e.g., a metal organic chemical vapor deposition(MOCVD) process, a hydride vapor phase epitaxy (HVPE) process, or amolecular beam epitaxy (MBE) process.

A first sub-electrode layer 122 may be formed on an entire top surfaceof the second semiconductor layer 116. For example, the firstsub-electrode layer 122 may be formed of a transparent conductive oxide.

Referring to FIGS. 2B and 8, a portion of the light-emitting structure110 may be etched to expose a portion of the first semiconductor layer112. Thus, the light-emitting structure 110 may be divided into thefirst region R1 exposing the top surface of the first semiconductorlayer 112, and the second region R2 not etched during the formation ofthe first region R1. The first region R1 may be formed in plurality, andthe plurality of first regions R1 may be two-dimensionally arranged. Thefirst sub-electrode layer 122 may be partially etched during theformation of the first region R1. Thus, a sidewall of the firstsub-electrode layer 122 may have a profile continuous with a sidewall ofthe second region R2.

Referring to FIGS. 2B and 9, the first insulating layer 124 may beformed on the light-emitting structure 110. The first insulating layer124 may cover the top surface of the first semiconductor layer 112 and atop surface of the first sub-electrode layer 122. The first insulatinglayer 124 may be formed of an insulating material having a lowerrefractive index than the second semiconductor layer 116 and/or may beformed to have an omnidirectional reflective (ODR) structure or adistributed Bragg reflective (DBR) structure. For example, the firstinsulating layer 124 may be formed of a silicon oxide (SiO₂) layer. Inanother example, the first insulating layer 124 may be formed to have astructure including silicon oxide (SiO₂) layers and titanium oxide(TiO₂) layers alternately and repeatedly stacked. In yet anotherexample, the first insulating layer 124 may have a structure includingsilicon oxide (SiO₂) layers and niobium oxide (Nb₂O₅) layers alternatelyand repeatedly stacked. The first insulating layer 124 may be formed bya deposition process, e.g., a chemical vapor deposition (CVD) process ora physical vapor deposition (PVD) process.

Next, the second openings OP2 may be formed in the first insulatinglayer 124. The second opening OP2 may penetrate the first insulatinglayer 124 to expose the top surface of the first sub-electrode layer122. The second openings OP2 may have the second width W2 and may beformed to be periodically arranged. The width and arrangementrelationship of the second openings OP2 may be the same as describedwith reference to FIGS. 2A to 6.

Referring to FIGS. 2B and 10, a second sub-electrode layer 126 may beformed to cover the top surface of the first insulating layer 124 on thesecond region R2 and to partially fill the second openings OP2. Thesecond sub-electrode layer 126 may be in contact with the firstsub-electrode layer 122. For example, a reflective metal layer may bedeposited on the growth substrate 100 by a deposition process such as aPVD process, and the deposited reflective metal layer may be patternedto form the second sub-electrode layer 126. The reflective metal layermay include, e.g., silver (Ag) or aluminum (Al). The secondsub-electrode layer 126 may expose the first insulating layer 124disposed on the first region R1. In certain embodiments, the secondsub-electrode layer 126 may completely fill the second openings OP2.

Referring to FIGS. 2B and 11, a second insulating layer 128 may beformed on the growth substrate 100 having the second sub-electrode layer126. The second insulating layer 128 may cover a top surface of thesecond sub-electrode layer 126 and a top surface of the first insulatinglayer 124 of the first region R1. The second insulating layer 128 mayinclude, e.g., a silicon oxide layer and may be formed by a depositionprocess such as a CVD process.

Subsequently, portions of the second and first insulating layers 128 and124 of the first region R1 may be removed to form the first opening OP1exposing the top surface of the first semiconductor layer 112. A portionof the second insulating layer 128 of the second region R2 may beremoved to form the third opening OP3 exposing the second sub-electrodelayer 126.

Referring to FIGS. 2B and 12, first and second reflective metal layers130 a and 130 b may be formed on the second insulating layer 128. Thefirst reflective metal layer 130 a may be formed to partially fill thefirst opening OP1 and to conformally cover an inner surface of the firstopening OP1. The second reflective metal layer 130 b may be formed to beconnected to the second sub-electrode layer 126 exposed through thethird opening OP3 on the second insulating layer 128 overlapping withthe second region R2. The second reflective metal layer 130 b may beelectrically insulated from the first reflective metal layer 130 a andthe first semiconductor layer 112.

Referring again to FIGS. 2A, 2B, 3A, and 3B, first and second metalinterconnections 142 and 144 may be formed. The first metalinterconnection 142 may be in contact with the first reflective metallayer 130 a, and the second metal interconnection 144 may be in contactwith the second reflective metal layer 130 b. The first and second metalinterconnections 142 and 144 may be spaced apart from each other and maybe electrically insulated from each other. For example, a metal layermay be formed on the resultant structure of FIG. 12 by a depositionprocess such as a PVD process, and the metal layer may be patterned toform the first and second metal interconnections 142 and 144. The metallayer may include at least one of, e.g., aluminum (Al), chromium (Cr),titanium (Ti), copper (Cu), or any alloy thereof.

Next, the protection layer 150 may be formed to partially expose thefirst and second metal interconnections 142 and 144, and first andsecond UBM patterns 152 and 154 may be formed on the first and secondmetal interconnections 142 and 144 exposed by the protection layer 150,respectively. Thus, the manufacture of the semiconductor light-emittingdevice 20 may be completed.

FIG. 13 is a schematic cross-sectional view illustrating a semiconductorlight-emitting device package according to some embodiments.Hereinafter, differences between the semiconductor light-emitting devicepackage of the present embodiment and the semiconductor light-emittingdevice packages 1 a and 1 b of FIGS. 1A and 1B will be mainly describedfor the purpose of ease and convenience in explanation.

Referring to FIG. 13, a semiconductor light-emitting device package 2according to some embodiments may include a mounting substrate 10 b, asemiconductor light-emitting device 20 a, and a sealing layer 30. Thesemiconductor light-emitting device 20 a may include the light-emittingstructure 110 and an electrode structure 160. The light-emittingstructure 110 may include the first and second semiconductor layers 112and 116 having different conductivity types, and the active layer 114disposed between the first and second semiconductor layers 112 and 116.The electrode structure 160 may include a first electrode 131electrically connected to the first semiconductor layer 122 and a secondelectrode 120 a electrically connected to the second semiconductor layer116.

The semiconductor light-emitting device 20 a may be mounted on a firstcircuit pattern 16 a of the mounting substrate 10 b with a conductiveadhesive member interposed therebetween. The conductive adhesive membermay electrically connect the first circuit pattern 16 a of the mountingsubstrate 10 b to the first electrode 131 of the semiconductorlight-emitting device 20 a. In the present embodiment, a partial regionof the light-emitting structure 110 may be completely removed to exposethe second electrode 120 a. A bonding pad BP for wire bonding may bedisposed on the exposed second electrode 120 a. A wire W mayelectrically connect the second electrode 120 a of the semiconductorlight-emitting device 20 a to a second circuit pattern 18 a of themounting substrate 10 b. The wire W may include, e.g., gold (Au).

The sealing layer 30 may seal the semiconductor light-emitting device 20a. For example, the sealing layer 30 may include a resin in which afluorescent substance is dispersed. The fluorescent substance mayinclude, e.g., a green fluorescent substance and/or a red fluorescentsubstance.

Electron-hole recombination may occur in the active layer 114 by anelectrical signal applied to the mounting substrate 10 b. Lightgenerated by the electron-hole recombination may be emitted upwardthrough the first semiconductor layer 112. The semiconductorlight-emitting device 20 a according to some embodiments will bedescribed hereinafter in more detail.

FIG. 14 is a schematic plan view illustrating the semiconductorlight-emitting device 20 a. FIG. 15 is a cross-sectional view takenalong line II-II′ of FIG. 14. Hereinafter, the same descriptions asexplained above will be omitted or mentioned briefly for the purpose ofease and convenience in explanation.

Referring to FIGS. 14 and 15, the semiconductor light-emitting device 20a may include the light-emitting structure 110 and the electrodestructure 160. In the present embodiment, the growth substrate 100 isremoved. The light-emitting structure 110 may include the first andsecond semiconductor layers 112 and 116 having different conductivitytypes, and the active layer 114 disposed between the first and secondsemiconductor layers 112 and 116. The first and second semiconductorlayers 112 and 116 may include the same materials as described withreference to FIGS. 2A, 2B, 3A, 3B, and 4A. The electrode structure 160may include the first electrode 131 disposed on a bottom surface of thesecond semiconductor layer 116, and the second electrode 120 a disposedbetween the first electrode 131 and the second semiconductor layer 116.

The light-emitting structure 110 may include the first region R1 and thesecond region R2. The first region R1 may correspond to an etched regionof the light-emitting structure 110, which is completely removed toexpose the second electrode 120 a of the electrode structure 160. Thesecond region R2 may correspond to a remaining region (i.e., a mesaregion) of the light-emitting structure 110, which is not etched duringthe formation of the first region R1.

The second electrode 120 a may include the first sub-electrode layer122, the first insulating layer 124, and the second sub-electrode layer126, which are sequentially stacked on the bottom surface of the secondsemiconductor layer 116. The first insulating layer 124 may include theplurality of second openings OP2, and the second sub-electrode layer 126may be in contact with the first sub-electrode layer 122 through thesecond openings OP2. The first sub-electrode layer 122, the firstinsulating layer 124, and the second sub-electrode layer 126 may havethe same or similar materials, structures, and/or components as thefirst sub-electrode layer 122, the first insulating layer 124, and thesecond sub-electrode layer 126 described with reference to FIGS. 2A, 2B,3A, 3B, and 4A, respectively. In addition, the second width W2, thesecond distance P2 and arrangement relationship of the second openingsOP2 may be the same or similar as described with reference to thesemiconductor light-emitting device 20. The second electrode 120 a mayfunction as the reflector layer having the multi-layered structure, likethe electrode 120 of the semiconductor light-emitting device 20. Eventhough not shown in the drawings, the embodiments of FIGS. 4B, 4C, 5A,5B, and 5C may also be applied to the semiconductor light-emittingdevice 20 a.

The second insulating layer 128 may be disposed between the secondelectrode 120 a and the first electrode 131 to electrically insulate thefirst and second electrodes 131 and 120 a from each other. The secondinsulating layer 128 may include, e.g., a silicon oxide layer.

The first electrode 131 may include a conductive adhesive layer 136 anda conductive substrate 138 which are sequentially stacked on a bottomsurface of the second insulating layer 128. The conductive adhesivelayer 136 may be formed of a conductive material, e.g., a metal layer.When the conductive adhesive layer 136 is the metal layer, the metallayer may include at least one of, but not limited to, Au, Ag, Pt, Ni,Cu, Sn, Al, Pb, Cr, or Ti. For example, the conductive substrate 138 mayinclude silicon, strained silicon, a silicon alloy, silicon-on-insulator(SOI), silicon carbide (SiC), silicon-germanium (SiGe),silicon-germanium carbide (SiGeC), germanium, a germanium alloy, galliumarsenide (GaAs), indium arsenide (InAs), a III-V group semiconductor, ora II-VI group semiconductor.

The first electrode 131 may be electrically connected to the firstsemiconductor layer 112 through a connection contact 134. The connectioncontact 134 may be disposed in a fourth opening OP4 which penetrates thesecond insulating layer 128, the second electrode 120 a, the secondsemiconductor layer 116, and the active layer 114 to expose the firstsemiconductor layer 112. The connection contact 134 may include a metalmaterial such as Cu, Al, or W. An insulating spacer 132 may be disposedbetween the connection contact 134 and a sidewall of the fourth openingOP4. The insulating spacer 132 may include a silicon oxide layer or asilicon nitride layer.

The connection contact 134 may be provided in plurality. In other words,the fourth opening OP4 may be provided in plurality. The plurality offourth openings OP4 may be two-dimensionally arranged along a firstdirection D1 and a second direction D2. Like the areas of the firstopenings OP1, areas of the fourth openings OP4 may also influence thelight efficiency of the semiconductor light-emitting device 20 a. Thefourth openings OP4 may have a smaller total area than the secondopenings OP2 in consideration of characteristics of the firstsemiconductor layer 112 having a lower electrical resistance than thesecond semiconductor layer 116. For example, a third width W3 of thefourth openings OP4 may be greater than the second width W2 of thesecond openings OP2, and a third distance P3 between the fourth openingsOP4 may be greater than the second distance P2 between the secondopenings OP2. Here, the third width W3 may correspond to the minimumwidth of the fourth opening OP4 (i.e., a width of a top end of thefourth opening OP4).

On the other hand, the fourth openings OP4 may penetrate the firstinsulating layer 124, and a portion of the fourth opening OP4penetrating the first insulating layer 124 may correspond to the firstopening OP1 described with reference to FIGS. 2A, 2B, 3A, 3B, and 4A.Since the third width W3 of the fourth opening OP4 is greater than thesecond width W2, the portion of the fourth opening OP4 penetrating thefirst insulating layer 124 may have a width greater than the secondwidth W2. As a result, the first insulating layer 124 may have aplurality of openings having different widths. A method formanufacturing the semiconductor light-emitting device 20 a will bedescribed hereinafter.

FIGS. 16 to 21 are cross-sectional views taken along the line II-II′ ofFIG. 14 to illustrate a method for manufacturing a semiconductorlight-emitting device, according to some embodiments. Hereinafter, thesame descriptions as explained above will be omitted or mentionedbriefly for the purpose of ease and convenience in explanation.

Referring to FIGS. 14 and 16, a light-emitting structure 110 may beformed on a growth substrate 100. The light-emitting structure 110 mayinclude a first semiconductor layer 112, an active layer 114, and asecond semiconductor layer 116, which are sequentially stacked on thegrowth substrate 100. Next, a first sub-electrode layer 122 and a firstinsulating layer 124 may be sequentially formed on the secondsemiconductor layer 116.

Referring to FIGS. 14 and 17, a plurality of second openings OP2exposing the first sub-electrode layer 122 may be formed in the firstinsulating layer 124. For example, the second openings OP2 may be formedto be periodically arranged on a residual region of the light-emittingstructure 110 except a region (i.e., a first region R1), to be etched,of the light-emitting structure 110. The second openings OP2 may have asecond width W2.

Referring to FIGS. 14 and 18, a second sub-electrode layer 126 may beformed to cover a top surface of the first insulating layer 124 and topartially fill the second openings OP2. The second sub-electrode layer126 may conformally cover the top surface of the first insulating layer124 and inner surfaces of the second openings OP2. Next, a secondinsulating layer 128 may be formed on the second sub-electrode layer126.

Referring to FIGS. 14 and 19, fourth openings OP4 may be formed topenetrate the second insulating layer 128, the second electrode 120 a,the second semiconductor layer 116, and the active layer 114. The fourthopenings OP4 may expose the first semiconductor layer 112. The fourthopenings OP4 may have a third width W3 greater than the second width W2and may be two-dimensionally arranged.

Referring to FIGS. 14 and 20, insulating spacers 132 may be formed onsidewalls of the fourth openings OP4, respectively. For example, aninsulating spacer layer may be formed on the growth substrate 100 toconformally cover inner surfaces of the fourth openings OP4, and ablanket anisotropic etching process may be performed on the insulatingspacer layer to form the insulating spacers 132. The blanket anisotropicetching process may be performed until bottom surfaces of the fourthopenings OP4 (i.e., the top surface of the first semiconductor layer112) is exposed. The insulating spacer layer may include, for example, asilicon oxide layer or a silicon nitride layer.

Referring to FIGS. 14 and 21, connection contacts 134 may be formed inthe fourth openings OP4, respectively. For example, a conductive layermay be formed on the growth substrate 100 to fill the fourth openingsOP4, and a planarization process may be performed on the conductivelayer to form the connection contacts 134. For example, the conductivelayer may include a metal material such as Cu, Al, or W.

Subsequently, a conductive substrate 138 may be bonded onto the growthsubstrate 100 with a conductive adhesive layer 136 interposedtherebetween. Next, the growth substrate 100 may be removed by, forexample, a laser lift-off process. The conductive substrate 138 maysupport the light-emitting structure 110 in subsequent processes.

Referring again to FIGS. 14 and 15, a partial region of thelight-emitting structure 110 may be completely removed to form a firstregion R1 exposing the first sub-electrode layer 122. Thereafter, abonding pad BP may be formed on the first sub-electrode layer 112exposed by the first region R1. Thus, the manufacture of thesemiconductor light-emitting device 20 a of FIG. 15 may be completed.

FIG. 22 is a cross-sectional view corresponding to the line II-II′ ofFIG. 14 to illustrate a semiconductor light-emitting device according tosome embodiments. Hereinafter, differences between a semiconductorlight-emitting device of the present embodiment and the semiconductorlight-emitting device 20 a of FIGS. 14 and 15 will be mainly describedfor the purpose of ease and convenience in explanation.

Referring to FIGS. 14 and 22, the second insulating layer 128 betweenthe second electrode 120 a and the first electrode 131 may extend intothe fourth openings OP4. The second insulating layer 128 may partiallyfill each of the fourth openings OP4 and may expose the firstsemiconductor layer 112.

A connection metal layer 134 a may be conformally disposed along aprofile of the second insulating layer 128 and may be in contact withthe first semiconductor layer 112 exposed by the fourth openings OP4. Inother words, unlike the connection contact 134 of FIG. 15, theconnection metal layer 134 a may partially fill each of the fourthopenings OP4 and may extend between the second insulating layer 128 andthe first electrode 131. Thus, a contact area between the firstelectrode 131 and the connection metal layer 134 a may be increased. Theconnection metal layer 134 a may include the same material (i.e., themetal material such as Cu, Al, or W) as the connection contact 15.

The first electrode 131 may be disposed on the connection metal layer134 a. The first electrode 131 may be electrically connected to thefirst semiconductor layer 112 through the connection metal layer 134 a.In the present embodiment, the connection metal layer 134 a maypartially fill the fourth openings OP4, and thus empty spaces (e.g., airgaps) AG may be defined in the fourth openings OP4.

FIGS. 23 to 25 are cross-sectional views corresponding to the lineII-II′ of FIG. 14 to illustrate a method for manufacturing asemiconductor light-emitting device, according to some embodiments.Hereinafter, the same descriptions as explained above will be omitted ormentioned briefly for the purpose of ease and convenience inexplanation.

Referring to FIGS. 14 and 23, a patterning process may be performed onthe resultant structure of FIG. 16 to form fourth openings OP4. Thefourth openings OP4 may sequentially penetrate the first insulatinglayer 124, the first sub-electrode layer 122, the second semiconductorlayer 116, and the active layer 114 to expose the first semiconductorlayer 112. The fourth openings OP4 may have a third width W3 and may betwo-dimensionally arranged.

Referring to FIGS. 14 and 24, a plurality of second openings OP2exposing the first sub-electrode layer 122 may be formed in the firstinsulating layer 124. The second openings OP2 may be formed to beperiodically arranged on a residual region of the light-emittingstructure 110 except a region (i.e., a first region R1), to be etched,of the light-emitting structure 110. The second openings OP2 may have asecond width W2 smaller than the third width W3.

Next, a second sub-electrode layer 126 may be formed to cover a topsurface of the first insulating layer 124 and to partially fill thesecond openings OP2. The second sub-electrode layer 126 may conformallycover the top surface of the first insulating layer 124 and innersurfaces of the second openings OP2.

Referring to FIGS. 14 and 25, a second insulating layer 128 may beformed to cover the second sub-electrode layer 126 and to extend ontosidewalls of the fourth openings OP4. The second insulating layer 128may partially fill the fourth openings OP4 and may expose the firstsemiconductor layer 112.

A connection metal layer 134 a may be formed on the second insulatinglayer 128. The connection metal layer 134 a may be conformally formedalong a profile of the second insulating layer 128 so as to be incontact with the first semiconductor layer 112 exposed by the fourthopenings OP4. The connection metal layer 134 a may partially fillresidual regions of the fourth openings OP4 in which the secondinsulating layer 128 is formed. Next, a conductive substrate 138 may bebonded to the growth substrate 100 with a conductive adhesive layer 136interposed therebetween. Next, the growth substrate 100 may be removedby, for example, a laser lift-off process. The conductive substrate 138may support the light-emitting structure 110 in subsequent processes.

Referring again to FIGS. 14 and 22, a partial region of thelight-emitting structure 110 may be completely removed to form a firstregion R1 exposing the first sub-electrode layer 122. Thereafter, abonding pad BP may be formed on the first sub-electrode layer 112exposed by the first region R1. Thus, the manufacture of thesemiconductor light-emitting device of FIG. 22 may be completed.

According to some embodiments, the reflector layer having themulti-layered structure including the sub-electrode layers, the firstand second insulating layers, and the reflective metal layers may beprovided on the light-emitting structure. Thus, the reflectivity of thesemiconductor light-emitting device may be improved to increase thelight extraction efficiency. In particular, the first insulating layermay have a lower refractive index than the semiconductor layer of thelight-emitting structure or may have the ODR or DBR structure, and thusthe reflected amount of light may be larger than the absorbed amount oflight when light emitted from the active layer reaches the firstinsulating layer. In addition, the widths and arrangement relationshipsof the openings of the first insulating layer may be realized to improvethe electrical characteristics of the semiconductor light-emittingdevice without influence on the light extraction efficiency of thesemiconductor light-emitting device. As a result, the semiconductorlight-emitting device with improved light efficiency and reliability maybe provided, thereby allowing implementation of light sources forlarge-sized, high-power, and high-efficiency products.

Example embodiments have been disclosed herein, and although specificterms are employed, they are used and are to be interpreted in a genericand descriptive sense only and not for purpose of limitation. In someinstances, as would be apparent to one of ordinary skill in the art asof the filing of the present application, features, characteristics,and/or elements described in connection with a particular embodiment maybe used singly or in combination with features, characteristics, and/orelements described in connection with other embodiments unless otherwisespecifically indicated. Accordingly, it will be understood by those ofskill in the art that various changes in form and details may be madewithout departing from the spirit and scope of the present invention asset forth in the following claims.

What is claimed is:
 1. A semiconductor light-emitting device,comprising: a light-emitting structure including a first semiconductorlayer, an active layer, and a second semiconductor layer which aresequentially stacked; a first sub-electrode layer on the secondsemiconductor layer; a first insulating layer on the first sub-electrodelayer; a second sub-electrode layer on the first insulating layer; asecond insulating layer on the second sub-electrode layer; a pluralityof first openings penetrating the first insulating layer and the secondinsulating layer to expose the first semiconductor layer; a plurality ofsecond openings penetrating the first insulating layer, the secondsub-electrode layer being connected to the first sub-electrode layerthrough the plurality of second openings; a third opening penetratingthe second insulating layer to expose the second sub-electrode layer; afirst electrode on the second insulating layer, the first electrodebeing connected to the first semiconductor layer through the pluralityof first openings; and a second electrode on the second insulatinglayer, the second electrode being connected to the second sub-electrodelayer through the third opening, wherein one of the plurality of secondopenings has a first diameter measured at a bottom surface of the firstinsulating layer, and a second diameter measured at a top surface of thefirst insulating layer, the second diameter being greater than the firstdiameter, and the first diameter being between 1 μm and 10 μm, wherein afirst pitch between two adjacent second openings of the plurality ofsecond openings closest to each other is between 10 μm and 50 μm,wherein one of the plurality of first openings has a third diametermeasured at a top surface of the first semiconductor layer, and a fourthdiameter measured at a top surface of the second insulating layer, thefourth diameter being greater than the second diameter, and the thirddiameter being greater than the first diameter, wherein in the pluralityof first openings, the first electrode extends along a side surface ofeach of the plurality of first openings, and wherein in the plurality ofsecond openings, the second sub-electrode layer and the secondinsulating layer extend along a side surface of each of the plurality ofsecond openings.
 2. The semiconductor light-emitting device as claimedin claim 1, wherein: in first one of the plurality of second openings,the second sub-electrode layer, the second insulating layer, and thefirst electrode extend along a side surface of the first one of theplurality of second openings, and in second one of the plurality ofsecond openings, the second sub-electrode layer, the second insulatinglayer, and the second electrode extend along a side surface of thesecond one of the plurality of second openings.
 3. The semiconductorlight-emitting device as claimed in claim 1, wherein: the light-emittingstructure includes: a mesa region, and a plurality of etched regionshaving a smaller thickness than the mesa region, the plurality of etchedregions exposing the first semiconductor layer, the first and secondinsulating layers cover the mesa region and the plurality of etchedregions, and the plurality of first openings penetrate the secondinsulating layer on each of the plurality of etched regions to exposethe first semiconductor layer.
 4. The semiconductor light-emittingdevice as claimed in claim 3, wherein the first electrode includes: afirst portion extending parallel to a side surface of the mesa region; asecond portion extending parallel to the side surface of the firstopening; a third portion connecting the first portion and the secondportion; and a fourth portion extending from the second portion andcovering the top surface of the first semiconductor.
 5. Thesemiconductor light-emitting device as claimed in claim 3, wherein: eachof the plurality of etched regions surrounds one of the plurality offirst openings, and the first insulating layer, the second insulatinglayer, and the first electrode extend along a side surface of theplurality of etched regions.
 6. The semiconductor light-emitting deviceas claimed in claim 3, wherein, at an edge of the mesa region, thesecond sub-electrode layer is on the first insulating layer, and thesecond sub-electrode layer and the first insulating layer have an offsetstack structure in a stepped shape tilted in a direction toward insideof the mesa region.
 7. The semiconductor light-emitting device asclaimed in claim 1, wherein the first electrode and the second electrodehave a same top level.
 8. The semiconductor light-emitting device asclaimed in claim 1, wherein the plurality of second openings arearranged in a first direction and a second direction perpendicular tothe first direction, and four adjacent second openings of the pluralityof second openings form a quadrilateral in a plan view.
 9. Thesemiconductor light-emitting device as claimed in claim 1, wherein theplurality of second openings are arranged in a zigzag form in a firstdirection or a second direction perpendicular to the first direction,and three second openings of the plurality of second openings form atriangle in a plan view.
 10. The semiconductor light-emitting device asclaimed in claim 1, wherein the plurality of first openings are arrangedin a first direction and a second direction intersecting the firstdirection thereby forming a plurality of rows and a plurality of columnsin a plan view.
 11. The semiconductor light-emitting device as claimedin claim 1, wherein the first sub-electrode layer includes a transparentconductive oxide, and the second sub-electrode layer includes areflective metal material.
 12. The semiconductor light-emitting deviceas claimed in claim 1, further comprising an additional transparentelectrode layer between the first insulating layer and the secondsub-electrode layer, and between the first sub-electrode layer and thesecond sub-electrode layer.
 13. A semiconductor light-emitting device,comprising: a light-emitting structure including a first semiconductorlayer, an active layer, and a second semiconductor layer which aresequentially stacked; a first sub-electrode layer on the secondsemiconductor layer; a first insulating layer on the first sub-electrodelayer; a second sub-electrode layer on the first insulating layer; asecond insulating layer on the second sub-electrode layer; a pluralityof first openings penetrating the first insulating layer and the secondinsulating layer to expose the first semiconductor layer; a plurality ofsecond openings penetrating the first insulating layer, the secondsub-electrode layer being in contact with the first sub-electrode layerthrough the plurality of second openings; a third opening penetratingthe second insulating layer to expose the second sub-electrode layer; afirst electrode on the second insulating layer, the first electrodebeing in contact with the first semiconductor layer through theplurality of first openings; and a second electrode on the secondinsulating layer, the second electrode being in contact with the secondsub-electrode layer through the third opening; wherein one of theplurality of second openings has a first diameter measured at a bottomsurface of the first insulating layer, and a second diameter measured ata top surface of the first insulating layer, the second diameter beinggreater than the first diameter, and the first diameter being between 1μm and 10 μm, wherein a first pitch between two adjacent second openingsof the plurality of second openings closest to each other is between 10μm and 50 μm, and wherein one of the plurality of first openings has athird diameter measured at a top surface of the first semiconductorlayer, and a fourth diameter measured at a top surface of the secondinsulating layer, the fourth diameter being greater than the seconddiameter, and the third diameter being greater than the first diameter.14. The semiconductor light-emitting device as claimed in claim 13,wherein the first electrode conformally covers inner surfaces of theplurality of first openings.
 15. The semiconductor light-emitting deviceas claimed in claim 13, wherein the second insulating layer extends ontosidewalls and bottom surfaces of a plurality of etched regions of thelight-emitting structure corresponding to the plurality of firstopenings.
 16. The semiconductor light-emitting device as claimed inclaim 13, wherein the first and second insulating layers, and the firstelectrode conformally cover sidewalls of a plurality of etched regionsof the light-emitting structure corresponding to the plurality of firstopenings.
 17. A semiconductor light-emitting device, comprising: alight-emitting structure including a first semiconductor layer, anactive layer, and a second semiconductor layer which are sequentiallystacked; a first sub-electrode layer on the second semiconductor layer;a first insulating layer on the first sub-electrode layer; a secondsub-electrode layer on the first insulating layer; a second insulatinglayer on the second sub-electrode layer; a plurality of first openingspenetrating the first insulating layer and the second insulating layerto expose the first semiconductor layer; a plurality of second openingspenetrating the first insulating layer, the second sub-electrode layerbeing in contact with the first sub-electrode layer through theplurality of second openings; a third opening penetrating the secondinsulating layer to expose the second sub-electrode layer; a firstelectrode on the second insulating layer, the first electrode being incontact with the first semiconductor layer through the plurality offirst openings; and a second electrode on the second insulating layer,the second electrode being in contact with the second sub-electrodelayer through the third opening; wherein one of the plurality of secondopenings has a first diameter measured at a bottom surface of the firstinsulating layer, and a second diameter measured at a top surface of thefirst insulating layer, the second diameter being greater than the firstdiameter, and the first diameter being between 1 μm and 10 μm, wherein afirst pitch between two adjacent second openings of the plurality ofsecond openings closest to each other is between 10 μm and 50 μm, andwherein one of the plurality of the first openings has a third diametermeasured at a top surface of the first semiconductor layer, and a fourthdiameter measured at a top surface of the second insulating layer, thefourth diameter being greater than the second diameter, and the thirddiameter being greater than the first diameter, wherein the secondsub-electrode layer conformally covers an inner surface of the pluralityof second openings, and wherein the first electrode conformally coversan inner surface of the plurality of first openings.
 18. Thesemiconductor light-emitting device as claimed in claim 17, wherein eachof widths of the plurality of first openings and widths of the pluralityof second openings becomes progressively smaller in a direction orientedtoward the first semiconductor layer.
 19. The semiconductorlight-emitting device as claimed in claim 17, wherein the secondsub-electrode layer completely fills the plurality of second openings.20. The semiconductor light-emitting device as claimed in claim 17,wherein the plurality of first openings are arranged in a firstdirection and a second direction intersecting the first direction todefine a plurality of rows and a plurality of columns.